#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "backend.h"
#include "tree.h"
#include "gimple.h"
#include "cfghooks.h"
#include "tree-pass.h"
#include "ssa.h"
#include "gimple-pretty-print.h"
#include "fold-const.h"
#include "stor-layout.h"
#include "cfganal.h"
#include "gimple-iterator.h"
#include "tree-cfg.h"
#include "cfgloop.h"
#include "tree-eh.h"
#include "tree-ssa-live.h"
#include "tree-dfa.h"

Include dependency graph for tree-ssa-sink.cc:

Data Structures
struct	[struct].sink_stats

Functions
static basic_block	find_bb_for_arg (gphi *phi, tree def)
static bool	all_immediate_uses_same_place (def_operand_p def_p)
static basic_block	nearest_common_dominator_of_uses (def_operand_p def_p, bool *debug_stmts)
static bool	do_not_sink (gimple *stmt, basic_block early_bb, basic_block best_bb)
static basic_block	select_best_block (basic_block early_bb, basic_block late_bb, gimple *stmt)
static bool	statement_sink_location (gimple stmt, basic_block frombb, gimple_stmt_iterator togsi, bool *zero_uses_p, virtual_operand_live &vop_live)
static unsigned	sink_common_stores_to_bb (basic_block bb)
static unsigned	sink_code_in_bb (basic_block bb, virtual_operand_live &vop_live)
gimple_opt_pass *	make_pass_sink_code (gcc::context *ctxt)

Variables
static struct	sink_stats

Function Documentation

◆ all_immediate_uses_same_place()

bool all_immediate_uses_same_place ( def_operand_p def_p )

static

When the first immediate use is in a statement, then return true if all
immediate uses in IMM are in the same statement.
We could also do the case where  the first immediate use is in a phi node,
and all the other uses are in phis in the same basic block, but this
requires some expensive checking later (you have to make sure no def/vdef
in the statement occurs for multiple edges in the various phi nodes it's
used in, so that you only have one place you can sink it to.

References all_immediate_uses_same_place(), DEF_FROM_PTR, FOR_EACH_IMM_USE_FAST, is_gimple_debug(), NULL, and USE_STMT.

Referenced by all_immediate_uses_same_place(), and statement_sink_location().

◆ do_not_sink()

bool do_not_sink	(	gimple *	stmt,
		basic_block	early_bb,
		basic_block	best_bb )

static

Return whether sinking STMT from EARLY_BB to BEST_BB should be avoided.

References bb_has_abnormal_pred(), CDI_DOMINATORS, cfun, do_not_sink(), dominated_by_p(), empty_block_p(), gimple_vdef(), gimple_vuse(), loop::inner, loop::latch, basic_block_def::loop_father, loop_outer(), and PROP_loop_opts_done.

Referenced by do_not_sink(), and select_best_block().

◆ find_bb_for_arg()

basic_block find_bb_for_arg	(	gphi *	phi,
		tree	def )

static

Given a PHI, and one of its arguments (DEF), find the edge for
that argument and return it.  If the argument occurs twice in the PHI node,
we return NULL.

References find_bb_for_arg(), gimple_phi_arg_edge(), gimple_phi_num_args(), i, NULL, and PHI_ARG_DEF.

Referenced by find_bb_for_arg(), and statement_sink_location().

◆ make_pass_sink_code()

gimple_opt_pass * make_pass_sink_code ( gcc::context * ctxt )

References make_pass_sink_code().

Referenced by make_pass_rename_ssa_copies(), and make_pass_sink_code().

◆ nearest_common_dominator_of_uses()

basic_block nearest_common_dominator_of_uses	(	def_operand_p	def_p,
		bool *	debug_stmts )

static

Find the nearest common dominator of all of the immediate uses in IMM.

References BASIC_BLOCK_FOR_FN, bitmap_first_set_bit(), bitmap_set_bit, CDI_DOMINATORS, cfun, DEF_FROM_PTR, dyn_cast(), ENTRY_BLOCK_PTR_FOR_FN, EXECUTE_IF_SET_IN_BITMAP, FOR_EACH_IMM_USE_FAST, gimple_bb(), gimple_phi_arg_edge(), basic_block_def::index, is_gimple_debug(), nearest_common_dominator(), nearest_common_dominator_of_uses(), NULL, PHI_ARG_INDEX_FROM_USE, and USE_STMT.

Referenced by nearest_common_dominator_of_uses(), and statement_sink_location().

◆ select_best_block()

basic_block select_best_block	(	basic_block	early_bb,
		basic_block	late_bb,
		gimple *	stmt )

static

Given EARLY_BB and LATE_BB, two blocks in a path through the dominator
tree, return the best basic block between them (inclusive) to place
statements.

We want the most control dependent block in the shallowest loop nest.

If the resulting block is in a shallower loop nest, then use it.

References profile_probability::always(), bb_loop_depth(), CDI_DOMINATORS, CDI_POST_DOMINATORS, do_not_sink(), dominated_by_p(), basic_block_def::flags, gcc_checking_assert, get_immediate_dominator(), select_best_block(), single_pred_edge(), and single_pred_p().

Referenced by select_best_block(), and statement_sink_location().

◆ sink_code_in_bb()

unsigned sink_code_in_bb	(	basic_block	bb,
		virtual_operand_live &	vop_live )

static

Perform code sinking on BB

References CDI_DOMINATORS, cfun, dominated_by_p(), dump_file, first_dom_son(), FOR_EACH_EDGE, FOR_EACH_IMM_USE_ON_STMT, FOR_EACH_IMM_USE_STMT, gimple_bb(), gimple_vdef(), gimple_vuse(), gsi_bb(), gsi_end_p(), gsi_last_bb(), gsi_move_before(), gsi_move_to_bb_end(), gsi_prev(), gsi_remove(), gsi_stmt(), basic_block_def::index, NULL, print_gimple_stmt(), release_defs(), SET_USE, sink_code_in_bb(), sink_common_stores_to_bb(), sink_stats, statement_sink_location(), stmt_could_throw_p(), basic_block_def::succs, and TDF_VOPS.

Referenced by sink_code_in_bb().

◆ sink_common_stores_to_bb()

unsigned sink_common_stores_to_bb ( basic_block bb )

static

Very simplistic code to sink common stores from the predecessor through
our virtual PHI.  We do this before sinking stmts from BB as it might
expose sinking opportunities of the merged stores.
Once we have partial dead code elimination through sth like SSU-PRE this
should be moved there.

References add_phi_arg(), cfun, create_phi_node(), dump_enabled_p(), dump_generic_expr(), dump_printf(), dump_printf_loc(), EDGE_COUNT, EDGE_PRED, FOR_EACH_IMM_USE_FAST, get_virtual_phi(), gimple_assign_lhs(), gimple_assign_rhs1(), gimple_assign_set_rhs1(), gimple_clobber_p(), gimple_phi_arg_def(), gimple_phi_arg_edge(), gimple_phi_num_args(), gimple_phi_result(), gimple_phi_set_result(), gimple_set_vdef(), gimple_set_vuse(), gimple_vdef(), gimple_vop(), gsi_after_labels(), gsi_for_stmt(), gsi_insert_before(), gsi_remove(), GSI_SAME_STMT, i, is_gimple_assign(), is_gimple_reg_type(), make_ssa_name(), MSG_OPTIMIZED_LOCATIONS, NULL, operand_equal_p(), basic_block_def::preds, release_defs(), sink_common_stores_to_bb(), sink_stats, SSA_NAME_DEF_STMT, stmt_can_throw_internal(), stmt_references_abnormal_ssa_name(), TDF_SLIM, TODO_cleanup_cfg, TREE_TYPE, TREE_VISITED, UNKNOWN_LOCATION, unlink_stmt_vdef(), and USE_STMT.

Referenced by sink_code_in_bb(), and sink_common_stores_to_bb().

◆ statement_sink_location()

bool statement_sink_location	(	gimple *	stmt,
		basic_block	frombb,
		gimple_stmt_iterator *	togsi,
		bool *	zero_uses_p,
		virtual_operand_live &	vop_live )

static

Given a statement (STMT) and the basic block it is currently in (FROMBB),
determine the location to sink the statement to, if any.
Returns true if there is such location; in that case, TOGSI points to the
statement before that STMT should be moved.

References all_immediate_uses_same_place(), ao_ref_init(), as_a(), CDI_DOMINATORS, CDI_POST_DOMINATORS, cfun, DECL_HARD_REGISTER, DEF_FROM_PTR, dominated_by_p(), ECF_CONST, ECF_LOOPING_CONST_OR_PURE, ECF_PURE, ECF_RETURNS_TWICE, EXIT_BLOCK, find_bb_for_arg(), basic_block_def::flags, FOR_EACH_IMM_USE_FAST, FOR_EACH_SSA_USE_OPERAND, get_immediate_dominator(), virtual_operand_live::get_live_in(), gimple_assign_rhs1(), gimple_assign_single_p(), gimple_bb(), gimple_call_flags(), gimple_get_lhs(), gimple_has_lhs(), gimple_has_side_effects(), gimple_vdef(), gimple_vuse(), gsi_after_labels(), has_zero_uses(), is_a(), is_gimple_assign(), is_gimple_call(), is_gimple_debug(), nearest_common_dominator_of_uses(), NULL, NULL_DEF_OPERAND_P, NULL_USE_OPERAND_P, operand_equal_p(), ref_maybe_used_by_stmt_p(), select_best_block(), single_ssa_def_operand(), single_succ(), single_succ_p(), SSA_NAME_OCCURS_IN_ABNORMAL_PHI, SSA_OP_ALL_DEFS, SSA_OP_ALL_USES, statement_sink_location(), stmt_ends_bb_p(), stmt_kills_ref_p(), stmt_may_clobber_ref_p_1(), TREE_TYPE, TYPE_MODE, USE_FROM_PTR, USE_STMT, VAR_P, and virtual_operand_p().